The invention relates to a valve assembly and to a seat adjusting device. The invention relates in particular to a valve assembly operative to supply a fluid, in particular a gas, to an inflatable chamber of a seat adjusting device.
Lumbar supports, side supports or other adjustable supports as well as massage units are frequently provided in seats to enhance an occupant's comfort when seated on the seat. Lumbar support devices are provided in backrests in order to provide adequate support in the lumbar vertebral or lordosis region of a person sitting on the seat by forming a suitable support surface. Side supports are provided on a backrest and/or on a seat portion to provide adjustable side support. The latter may be desirable not only to accommodate varying occupant sizes, but also to actively adjust lateral support in response to centrifugal forces. Massage units may be integrated into a seat to stimulate blood circulation and/or to further enhance occupant comfort.
Some implementations of seat adjusting devices utilize one or plural inflatable fluid chambers. The fluid chambers may be configured as inflatable cushions or bladders which change their shape and/or size in dependence on an amount of fluid contained therein. Examples for seats having lumbar support devices implemented using inflatable fluid chambers are described, for example in EP 1 072 465 A1 or in DE 100 63 478 A1. An adjustment of the adjustable support may be effected by means of a pressure source and a suitably configured pneumatic circuit comprising valves and connecting members, such as hoses.
The integration of an increasing number of adjustable components into a seat enhances sitting comfort. On the other hand, installation space available in the seat is limited. Further, the integration of an increasing number of actuators and associated componentry required to couple the actuator to a mechanically or pneumatically adjustable member leads to an increase of assembly time and, thus, assembly costs. While pneumatic elements, such as valves, may enhance life time of and/or comfort provided by the adjustable support device, such components may add to installation space and cost.
In order to address problems associates with installation space, installation time and installation cost, a plurality of valves can be assembled to form a valve battery, which may be pre-assembled prior to installation in a seat. DE 44 13 657 C1 describes an example for a valve battery having a modular configuration, with one valve being integrated into each module and plural modules being combined to form the valve battery.
In order to further reduce the number of components which need to be assembled, fluid channels may be integrated into a solid member of a valve battery housing. While this allows the time required for assembling the valve battery to be reduced, such a design may suffer from a reduced design flexibility. For illustration, for a given design of the valve battery housing, the configuration of channels formed in the valve battery housing may invariably determine the types of valves which may be installed in the housing. In consequence, it may be required to produce and supply different valve battery housings depending on whether 3/2-valves, 3/3-valves or 2/2-valves or specific combinations thereof are to be installed in the valve battery housing, which in turn adds to costs.